Magnesiochloritoid

General Information:
 Chemical Formula:
MgAl2SiO5(OH)2
 Composition:
(Molecular Weight = 220.37 gm)
Magnesium 11.03 % Mg
Aluminum 24.49 % Al
Silicon 12.74 % Si
Hydrogen 0.91 % H 
Oxygen 50.82 % O 
 Empirical Formula:
MgAl2SiO5(OH)2
 IMA Status:
Approved IMA
Physical Properties:
 Cleavage:
[001] Perfect, [110] Distinct
 Color:
greenish gray or greenish black.
 Density:
3.5 - 3.6, Average = 3.55
 Diaphaniety:
Translucent
 Hardness:
6.5 - Pyrite
 Luster:
Pearly
 Streak:
gray white
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